The sensitivity tests of Mycobacteria against various drug concentrations most vital for deter mining drugs for choice, but here in this report the auther studied whether it is possible or not to differentiate the species of Mycobacteria by observing the results of routine drug sensitivity tests and thereby intended to establish resistance pattern of each species without having the aid of any specific reagent or implementation of other procedures. * M .intracellulare=M.avium-intracellulare complex.